Expanding tube coupling for reversible lead locking

ABSTRACT

A device for extending a lead according to some embodiments includes a body, a tubular member coupled to the body, the tubular member comprising an outer surface, wherein the outer surface is sized to insert into an inner lumen of a lead, the tubular member is movable between a first configuration in which the tubular member slides into the lead, and a second configuration in which at least a portion of the tubular member expands to engage an inner surface of the lead; and, an actuation mechanism operatively coupled to the tubular member, the actuation mechanism configured to move the tubular member between the first configuration and second configuration.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. application Ser. No.16/805,745, filed Feb. 29, 2020, entitled EXPANDING COIL COUPLING FORLEAD EXTENSION AND EXTRACTION, now U.S. Pat. No. 11,357,977, which is acontinuation of U.S. application Ser. No. 15/856,355, filed Dec. 28,2017, entitled EXPANDING COIL COUPLING FOR LEAD EXTENSION ANDEXTRACTION, now U.S. Pat. No. 10,576,274, which claims the benefit ofand priority to, under 35 U.S.C. § 119(e), U.S. Provisional ApplicationSer. No. 62/440,211, filed Dec. 29, 2016, entitled EXPANDING TUBECOUPLING FOR REVERSIBLE LEAD LOCKING, which are all hereby incorporatedby reference in their entirety for all purposes. U.S. application Ser.No. 15/856,355 is also a continuation-in-part of U.S. application Ser.No. 14/954,169, filed Nov. 30, 2015, entitled COLLAPSING COIL COUPLINGFOR LEAD EXTENSION AND EXTRACTION, now U.S. Pat. No. 9,731,113, whichclaims the benefit of and priority to, under 35 U.S.C. § 119(e), U.S.Provisional Application Ser. No. 62/098,214, filed Dec. 30, 2014,entitled COLLAPSING COIL COUPLING FOR LEAD EXTENSION AND EXTRACTION,which are all hereby incorporated by reference in their entirety for allpurposes.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to lead extension and leadlocking, and more specifically to methods and devices for extendingwithin a lead and/or locking within a lead to provide structure overwhich a lead extraction device may be passed.

BACKGROUND

Surgically implanted cardiac pacing systems, such as pacemakers anddefibrillators, play an important role in the treatment of heartdisease. In the 50 years since the first pacemaker was implanted,technology has improved dramatically, and these systems have saved orimproved the quality of countless lives. Pacemakers treat slow heartrhythms by increasing the heart rate or by coordinating the heart'scontraction for some heart failure patients. Implantablecardioverter-defibrillators stop dangerous rapid heart rhythms bydelivering an electric shock.

Cardiac pacing systems typically include a timing device and a lead,which are placed inside the body of a patient. One part of the system isthe pulse generator containing electric circuits and a battery, usuallyplaced under the skin on the chest wall beneath the collarbone. Toreplace the battery, the pulse generator must be changed by a simplesurgical procedure every 5 to 10 years. Another part of the systemincludes the wires, or leads, which run between the pulse generator andthe heart. In a pacemaker, these leads allow the device to increase theheart rate by delivering small timed bursts of electric energy to makethe heart beat according to a healthy rhythm. In a defibrillator, thelead has special coils to allow the device to deliver a high-energyshock and convert potentially dangerous rapid rhythms (ventriculartachycardia or fibrillation) back to a normal rhythm. Additionally, theleads may transmit information about the heart's electrical activity tothe pacemaker.

For both of these functions, leads must be in contact with heart tissue.Most leads pass through a vein under the collarbone that connects to theright side of the heart (right atrium and right ventricle). In somecases, a lead is inserted through a vein and guided into a heart chamberwhere it is attached with the heart. In other instances, a lead isattached to the outside of the heart. To remain attached to the heartmuscle, most leads have a fixation mechanism, such as a small screwand/or hooks at the end.

Within a relatively short time after a lead is implanted into the body,the body's natural healing process forms scar tissue along the lead andpossibly at its tip, thereby fastening it even more securely in thepatient's body. Leads usually last longer than device batteries, soleads are simply reconnected to each new pulse generator (battery) atthe time of replacement. Although leads are designed to be implantedpermanently in the body, occasionally these leads must be removed, orextracted. Leads may be removed from patients for numerous reasons,including but not limited to, infections, lead age, and leadmalfunction.

Removal or extraction of the lead may be difficult. The body's naturalhealing process forms scar tissue over and along the lead, and possiblyat its tip, thereby encasing at least a portion of the lead andfastening it even more securely in the patient's body. In addition, thelead and/or tissue may become attached to the vasculature wall. Bothresults may, therefore, increase the difficulty of removing the leadsfrom the patient's vasculature. Typical leads in a human may passthrough the innominate vein, past the superior vena cava (“SVC”), andinto the right atrium of the heart. Tissue growth occurring along theSVC and other locations along the innominate vein may increase the riskand difficulty in extracting the leads from such locations, particularlywhen the vein(s)′ walls are thin and the surrounding tissue is notablyfibrous.

A variety of tools have been developed to make lead extraction safer andmore successful. Current lead extraction techniques include mechanicaltraction, mechanical devices, and laser devices. Extracting a lead mayoften involve applying tension to the lead while it is still implanted,whether in order to pull it free using the tension force, to loosen it,and/or to apply an extraction device over the lead. Applying anextraction device over a lead which is not adequately tensioned mayresult in kinking or damage to the lead, for example at locations whichare not as easy to access as the proximal portion of the lead that wasnear to or coupled with the pacemaker or defibrillator. In extracting alead, the lead (including any conductive portions, insulating sheath,and/or casing layers) is often cut between the distal end of the leadand the proximal end of the lead (which is often coupled to thepacemaker). In other situations, the lead exhibits structural failure,either before, or during, the lead extraction surgical intervention.These situations may result in a lead that is not as long as theclinician would like it to be in order to both apply tension to the leadand/or deploy an extraction device over the lead. Existing leadextension technologies may be limited in the maximum level of tensionwhich they can support in coupling with the lead, with the reversibilityof such coupling, and/or with the reliability of such coupling.

SUMMARY

A device for extending a lead according to embodiments of the presentdisclosure includes a body; a coil element coupled to the body, the bodyconfigured to cover at least a portion of the coil element during use,the coil element including a plurality of coils forming an inner lumen,wherein the inner lumen is sized to receive an outer surface of a lead,the coil element is movable between a first configuration in which thecoil element slides over the lead, and a second configuration in whichat least some coils of the plurality of coils grip the outer surface ofthe lead; an actuation mechanism operatively coupled to the coilelement, the actuation mechanism configured to move the coil elementbetween the first and second configurations; and a tether coupled to thelead via one or more of the body, the coil element, and the actuationmechanism, the tether configured to extend further proximally than aproximal-most end of the lead, the tether further configured to transferat least a portion of a tension force applied to the tether to the leadvia the one or more of the body, the coil element, and the actuationmechanism.

In some cases, the actuation mechanism includes a first ratchet grip anda second ratchet grip, wherein the first ratchet grip is coupled to afirst end of the coil element, wherein the second ratchet grip iscoupled to a second end of the coil element, and wherein the actuationmechanism is configured to move the coil element between the first andsecond configurations via one or both of rotation of the first ratchetgrip along a first rotational direction relative to the second ratchetgrip, and rotation of the second ratchet grip along a second rotationaldirection relative to the first ratchet grip, wherein the first andsecond rotational directions are opposing rotational directions.

In some cases, the first ratchet grip engages the second ratchet grip ata unidirectional rotational coupling that permits rotation of the firstratchet grip along the first rotational direction relative to the secondratchet grip and rotation of the second ratchet grip along the secondrotational direction relative to the first ratchet grip while inhibitingrotation of the first ratchet grip along the second rotational directionrelative to the second ratchet grip and of the second ratchet grip alongthe first rotational direction relative to the first ratchet grip whilethe first ratchet grip is in the unidirectional rotational coupling withthe second ratchet grip. The unidirectional rotational coupling mayinclude one or more undercut or back-cut teeth formed on one or both ofthe first and second ratchet grips. A safety cap may be used andconfigured to cover the unidirectional rotational coupling.

In some cases, the first and second ratchet grips are axially separablefrom one another to release the unidirectional rotational coupling,thereby permitting the coil element to move from the secondconfiguration to the first configuration.

Embodiments of such devices may further include an outer sleeve, akeyway formed in one of the outer sleeve and the first ratchet grip, anda tab formed in the other of the outer sleeve and the first ratchetgrip, wherein torque is transmitted from the outer sleeve to the firstratchet grip via an interface between the keyway and the tab, the tabconfigured to break away from the outer sleeve at a level of appliedtorque.

In some cases, the actuation mechanism is itself the body or forms allor part of the body. In some embodiments, the body includes a firstsleeve and a second sleeve, wherein the first sleeve is coupled to afirst end of the coil element, wherein the second sleeve is coupled to asecond end of the coil element, and wherein the actuation mechanism isconfigured to move the coil element between the first and secondconfigurations via axial translation of the first sleeve along adirection relative to the second sleeve. The actuation mechanism mayfurther include a pin coupled to one of the first and second sleeves anda slot formed in another of the first and second sleeves, wherein theslot guides a path of translation of the first sleeve with respect tothe second sleeve.

In some cases, the slot includes a portion that imparts a tighteningtwist to the coil element in moving the coil element to the secondconfiguration. The slot may further include a portion that causestranslation of the first sleeve along a second direction relative to thesecond sleeve in moving the coil element to the second configuration,wherein the second direction is different from and/or opposite to thefirst direction.

According to some embodiments of the present disclosure, the pluralityof coils include coils of different pitch, such that some of theplurality of coils are configured to collapse to grip the lead at alower applied torque than others of the plurality of coils.

A method for extending a lead according to some embodiments of thepresent disclosure includes sliding a coil element over a lead when thecoil element is in a first configuration, the coil element comprising aplurality of coils forming an inner lumen sized to receive an outersurface of the lead; moving the coil element from the firstconfiguration into a second configuration in which at least some coilsof the coil element grip the outer surface of the lead; and applyingtension to the lead by applying tension to a tether that is coupled tothe lead via the coil element when the coil element is in the secondconfiguration.

An additional device for extending a lead or a lead locking deviceaccording to embodiments of the present disclosure includes a body, atubular member coupled to the body, the tubular member comprising anouter surface, wherein the outer surface is sized to insert into aninner lumen of a lead, the tubular member is movable between a firstconfiguration in which the tubular member slides into the lead, and asecond configuration in which at least a portion of the tubular memberexpands to engage an inner surface of the lead, and an actuationmechanism operatively coupled to the tubular member, the actuationmechanism configured to move the tubular member between the firstconfiguration and second configuration.

A device wherein the tubular member comprises a plurality of segments.

A device wherein at least some segments of the plurality of segmentsspringably release to sequentially engage the inner surface of the leadfrom a distal-most end of the lead to a proximal-most end of the lead.

A device wherein at least some segments of the plurality of segmentsspringably release to sequentially engage the inner surface of the leadfrom a proximal-most end of the lead to a distal-most end of the lead.

A device further comprising a tether coupled to the lead via one or moreof the body, the tubular member, and the actuation mechanism, the tetherconfigured to extend further proximally than a proximal-most end of thelead, the tether further configured to transfer at least a portion of atension force applied to the tether to the lead via the one or more ofthe body, the tubular member, and the actuation mechanism.

A device wherein the actuation mechanism comprises a first ratchet gripand a second ratchet grip, wherein the first ratchet grip is coupled toa first end of the tubular member, wherein the second ratchet grip iscoupled to a second end of the tubular member, and wherein the actuationmechanism is configured to move the tubular member between the first andsecond configurations via one or both of: rotation of the first ratchetgrip along a first rotational direction relative to the second ratchetgrip, and rotation of the second ratchet grip along a second rotationaldirection relative to the first ratchet grip, wherein the first andsecond rotational directions are opposing rotational directions.

A device wherein the first ratchet grip engages the second ratchet gripat a unidirectional rotational coupling that permits rotation of thefirst ratchet grip along the first rotational direction relative to thesecond ratchet grip and rotation of the second ratchet grip along thesecond rotational direction relative to the first ratchet grip whileinhibiting rotation of the first ratchet grip along the secondrotational direction relative to the second ratchet grip and of thesecond ratchet grip along the first rotational direction relative to thefirst ratchet grip while the first ratchet grip is in the unidirectionalrotational coupling with the second ratchet grip.

A device wherein the unidirectional rotational coupling includes one ormore undercut or back-cut teeth formed on one or both of the first andsecond ratchet grips.

A device wherein the first and second ratchet grips are axiallyseparable from one another to release the unidirectional rotationalcoupling, thereby permitting the tubular member to move from the secondconfiguration to the first configuration.

A device further comprising an inner sleeve, a keyway formed in one ofthe inner sleeve and the first ratchet grip, and a tab formed in theother of the inner sleeve and the first ratchet grip, wherein torque istransmitted from the inner sleeve to the first ratchet grip via aninterface between the keyway and the tab, the tab configured to breakaway from the inner sleeve at a level of applied torque.

A device wherein the actuation mechanism is the body.

A device wherein the body comprises a first sleeve and a second sleeve,wherein the first sleeve is coupled to a first end of the tubularmember, wherein the second sleeve is coupled to a second end of thetubular member, and wherein the actuation mechanism is configured tomove the tubular member between the first and second configurations viaaxial translation of the first sleeve along a direction relative to thesecond sleeve.

A device wherein the actuation mechanism further comprises a pin coupledto one of the first and second sleeves and a slot formed in another ofthe first and second sleeves, wherein the slot guides a path oftranslation of the first sleeve with respect to the second sleeve.

A device wherein the slot includes a portion that imparts a tighteningtwist to the tubular member in moving the tubular member to the secondconfiguration.

A device wherein the direction is a first direction, and wherein theslot includes a portion that causes translation of the first sleevealong a second direction relative to the second sleeve in moving thetubular member to the second configuration, wherein the second directionis different from the first direction.

A device wherein the second direction is opposite to the firstdirection.

A device wherein the plurality of segments include segments of differentpitch, such that some of the plurality of segments are configured toexpand to springably engage the lead at a lower applied torque thanothers of the plurality of segments.

An additional method for extending a lead or locking onto an interior ofa lead includes sliding a tubular member into a lead when the tubularmember is in a first configuration, the tubular member comprising anouter surface sized to insert into an inner lumen of the lead, movingthe tubular member from the first configuration into a secondconfiguration in which at least a portion of the tubular member expandsto engage the inner lumen of the lead by actuating an actuationmechanism operatively coupled to the tubular member, the actuationmechanism configured to move the tubular member between the firstconfiguration and the second configuration.

The method wherein the tubular member comprises a plurality of segments.

The method wherein at least some segments of the plurality of segmentsspringably release to sequentially engage the inner surface of the leadfrom a distal-most end of the lead to a proximal-most end of the lead orfrom a proximal-most end of the lead to a distal-most end of the lead.

The method wherein the actuation mechanism comprises a first ratchetgrip and a second ratchet grip, wherein the first ratchet grip iscoupled to a first end of the tubular member, wherein the second ratchetgrip is coupled to a second end of the tubular member, and whereinmanipulating the actuation mechanism to move the tubular member from thefirst configuration into the second configuration includes one or bothof: rotating the first ratchet grip along a first rotational directionrelative to the second ratchet grip, and rotating the second ratchetgrip along a second rotational direction relative to the first ratchetgrip, wherein the first and second rotational directions are opposingrotational directions.

The method wherein the tubular member includes a first end coupled to afirst sleeve and a second end coupled to a second sleeve, and whereinmanipulating the actuation mechanism to move the tubular member from thefirst configuration into the second configuration includes translatingthe first sleeve along a direction relative to the second sleeve.

The method wherein the actuation mechanism further comprises a pincoupled to one of the first and second sleeves and a slot formed inanother of the first and second sleeves, the slot guiding a path oftranslation of the first sleeve with respect to the second sleeve, andwherein manipulating the actuation mechanism to move the tubular memberfrom the first configuration into the second configuration causes theslot to impart a releasing twist to the tubular member.

The method wherein the plurality of segments include segments of a firstpitch and segments of a second pitch, and moving the tubular member fromthe first configuration into the second configuration includes releasingthe segments of the first pitch to springably engage the inner lumen ofthe lead at a first applied torque and releasing the segments of thesecond pitch to springably engage the inner lumen of the lead at asecond applied torque, the second applied torque being less than thefirst applied torque.

The phrases “at least one”, “one or more”, and “and/or” are open-endedexpressions that are both conjunctive and disjunctive in operation. Forexample, each of the expressions “at least one of A, B and C”, “at leastone of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B,or C” and “A, B, and/or C” means A alone, B alone, C alone, A and Btogether, A and C together, B and C together, or A, B and C together.When each one of A, B, and C in the above expressions refers to anelement, such as X, Y, and Z, or class of elements, such as X₁-X_(n),Y₁-Y_(m), and Z₁-Z_(o), the phrase is intended to refer to a singleelement selected from X, Y, and Z, a combination of elements selectedfrom the same class (e.g., X₁ and X₂) as well as a combination ofelements selected from two or more classes (e.g., Y₁ and Z_(o)).

The term “a” or “an” entity refers to one or more of that entity. Assuch, the terms “a” (or “an”), “one or more” and “at least one” may beused interchangeably herein. It is also to be noted that the terms“comprising”, “including”, and “having” may be used interchangeably.

A “lead” is a conductive structure, typically an electrically insulatedcoiled wire. The electrically conductive material may be any conductivematerial, with metals and intermetallic alloys common. The outer sheathof insulated material is biocompatible and bio stable (e.g.,non-dissolving in the body) and generally includes organic materialssuch as polyurethane and polyimide. Lead types include, by way ofnon-limiting example, epicardial and endocardial leads. Leads arecommonly implanted into a body percutaneously or surgically.

The term “means” as used herein shall be given its broadest possibleinterpretation in accordance with 35 U.S.C. Section 112(f). Accordingly,a claim incorporating the term “means” shall cover all structures,materials, or acts set forth herein, and all of the equivalents thereof.Further, the structures, materials or acts and the equivalents thereofshall include all those described in the summary of the invention, briefdescription of the drawings, detailed description, abstract, and claimsthemselves.

It should be understood that every maximum numerical limitation giventhroughout this disclosure is deemed to include each and every lowernumerical limitation as an alternative, as if such lower numericallimitations were expressly written herein. Every minimum numericallimitation given throughout this disclosure is deemed to include eachand every higher numerical limitation as an alternative, as if suchhigher numerical limitations were expressly written herein. Everynumerical range given throughout this disclosure is deemed to includeeach and every narrower numerical range that falls within such broadernumerical range, as if such narrower numerical ranges were all expresslywritten herein.

The preceding is a simplified summary of the disclosure to provide anunderstanding of some aspects of the disclosure. This summary is neitheran extensive nor exhaustive overview of the disclosure and its variousaspects, embodiments, and configurations. It is intended neither toidentify key or critical elements of the disclosure nor to delineate thescope of the disclosure but to present selected concepts of thedisclosure in a simplified form as an introduction to the more detaileddescription presented below. As will be appreciated, other aspects,embodiments, and configurations of the disclosure are possibleutilizing, alone or in combination, one or more of the features setforth above or described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are incorporated into and form a part of thespecification to illustrate several examples of the present disclosure.These drawings, together with the description, explain the principles ofthe disclosure. The drawings simply illustrate possible and alternativeexamples of how the disclosure may be made and used and are not to beconstrued as limiting the disclosure to only the illustrated anddescribed examples. Further features and advantages will become apparentfrom the following, more detailed, description of the various aspects,embodiments, and configurations of the disclosure, as illustrated by thedrawings referenced below.

FIG. 1 illustrates a top plan view of a coil element in a configurationfor sliding over a lead, according to an embodiment of the presentdisclosure.

FIG. 2 illustrates a top plan view of the coil element of FIG. 1 in adifferent configuration in which the coils of the coil element engagethe outer surface of the lead, according to an embodiment of the presentdisclosure.

FIG. 3 illustrates a perspective view of a ratchet body actuationmechanism for a coil element, according to an embodiment of the presentdisclosure.

FIG. 4 illustrates an exploded view of the ratchet body actuationmechanism of FIG. 3 , according to an embodiment of the presentdisclosure.

FIG. 5 illustrates a front perspective view of a cam actuation mechanismfor a coil element, according to an embodiment of the presentdisclosure.

FIG. 6 illustrates a partial front elevation view of the cam actuationmechanism of FIG. 5 showing an unwound and flattened depiction of thecam pathway, according to an embodiment of the present disclosure.

FIG. 7 illustrates an alternative coil element, according to anembodiment of the present disclosure.

FIG. 8 illustrates a side elevation view of an outer sleeve with abreakaway torque tab, according to an embodiment of the presentdisclosure.

FIG. 9 illustrates a side and front perspective view of the outer sleeveof FIG. 8 , according to an embodiment of the present disclosure.

FIG. 10 illustrates a front elevation view of a ratchet body actuationmechanism for a coil element, according to an embodiment of the presentdisclosure.

FIG. 11 illustrates a front detail view of the ratchet body actuationmechanism within line 11-11 of FIG. 10 and with internal componentsillustrated in dashed lines, according to an embodiment of the presentdisclosure.

FIG. 12A illustrates a partial perspective view of a tubular member,according to an embodiment of the present disclosure.

FIG. 12B illustrates a partial perspective view of a tubular member,according to an embodiment of the present disclosure.

FIG. 12C illustrates a top plan view of a tubular member, according toan embodiment of the present disclosure.

FIG. 12D illustrates a top plan view of the tubular member of FIG. 12Cin an expanded configuration, according to an embodiment of the presentdisclosure.

FIG. 13A illustrates a top plan view of a tubular member in anunexpanded configuration for sliding into a lead, according to anembodiment of the present disclosure.

FIG. 13B illustrates a top plan view of the tubular member of FIG. 13Ain an expanded configuration in which the segments of the tubular memberengage an inner surface of a lead, according to an embodiment of thepresent disclosure.

FIG. 14A illustrates a cross-sectional view of a tubular member disposedwithin a lead in an unexpanded configuration, according to an embodimentof the present disclosure.

FIG. 14B illustrates a cross-section view of the tubular member of FIG.14A in an expanded configuration in which the segments of the tubularmember engage the inner surface of the lead, according to an embodimentof the present disclosure.

FIG. 15 illustrates a front elevation view of a ratchet body actuationmechanism for a tubular member for inserting within a lead, according toan embodiment of the present disclosure.

FIG. 16A illustrates a perspective view of a ratchet body actuationmechanism for a tubular member, according to an embodiment of thepresent disclosure.

FIG. 16B illustrates an exploded view of the ratchet body actuationmechanism of FIG. 16A, according to an embodiment of the presentdisclosure.

FIG. 17A illustrates a front perspective view of a cam actuationmechanism for a tubular member, according to an embodiment of thepresent disclosure.

FIG. 17B illustrates a partial front elevation view of the cam actuationmechanism of FIG. 17A showing an unwound and flattened depiction of thecam pathway, according to an embodiment of the present disclosure.

It should be understood that the drawings are not necessarily to scale.In certain instances, details that are not necessary for anunderstanding of the disclosure or that render other details difficultto perceive may have been omitted. It should be understood, of course,that the disclosure is not necessarily limited to the particularembodiments illustrated herein.

DETAILED DESCRIPTION

Before any embodiments of the disclosure are explained in detail, it isto be understood that the disclosure is not limited in its applicationto the details of construction and the arrangement of components setforth in the following description or illustrated in the followingdrawings. The disclosure is capable of other embodiments and of beingpracticed or of being carried out in various ways. Also, it is to beunderstood that the phraseology and terminology used herein is for thepurpose of description and should not be regarded as limiting. The useof “including,” “comprising,” or “having” and variations thereof hereinis meant to encompass the items listed thereafter and equivalentsthereof as well as additional items.

FIG. 1 illustrates a top plan view of a coil element 2 (which may alsobe referred to as a hypotube) in a configuration for sliding over a lead4, according to an embodiment of the present disclosure. In theconfiguration of FIG. 1 , the coil element 2 includes a plurality ofcoils, and an inner lumen with an inner dimension or diameter that islarge enough to accept the lead 4 therethrough, such that the coilelement 2 may be placed over the lead 2 and/or slide freely over thelead. The segment of coil element 2 depicted may be a segment of a lasercut hypotube with an interrupted spiral cut (“ISC”) pattern. Theplurality of coils may be formed by, for example, ISC, coil cut pattern,and/or the like. The coil element 2 may be deformed from theconfiguration shown in FIG. 1 to the configuration shown in FIG. 2 inwhich some or all of the plurality of coils of the coil element 2 arecompressed or deformed such that they engage and grip with the outersurface of the lead 4. In some embodiments, the deformation of the coilelement 2 results in compressive force being applied to the lead 4.

The coil element 2 may be moved between a first configuration in whichthe coil element 2 slides over the lead 4 to a second configuration inwhich some or all of the coils of the coil element 2 grippingly engagethe outer surface of the lead in various ways. As one example, the coilelement 2 may be longitudinally pulled or stretched, thereby causing theinner diameter of the coils to shrink to the point at which the coilengages the lead 4. As another example, one end of the coil element 2may be rotated, twisted, or turned with respect to the other end of thecoil element 2 in order to cause a tightening of the windings of thecoils of the coil element 2, thereby shrinking their inner diameters tothe point at which the coil engages the lead 4.

FIG. 2 illustrates the coil element 2 in a deformed configuration, inwhich the deformed laser cut segment with ISC cut pattern has beendeformed over the lead 4. The coil element 2 has been deformed in orderto transform it into a traction tool. A trailing wire or tether (notshown), including for example high strength braided fibers, metal wires,and the like, may be attached to the coil element 2 to allow tension tobe applied to the coil element 2 from a control point away from the coilelement 2 and lead 4 itself.

FIGS. 3 and 4 illustrate one embodiment of a ratchet deployment device11, with an internal coil cut coil element 2 and ratchet grips 10, 12.In the embodiment shown in FIGS. 3 and 4 , ratchet grip 10 is coupled toend 8 of coil element 2 (e.g. by welding), and ratchet grip 12 iscoupled to end 6 of coil element 2 (e.g. by welding). Ratchet grips 10and 12 interface with each other at unidirectional rotational coupling14, which may be formed by teeth or other interengaging projections andindentations which permit ratchet grip 10 to rotate in direction D1 withrespect to ratchet grip 12, and which permit ratchet grip 12 to rotatein direction D2 with respect to ratchet grip 10, but which inhibitrotation of such ratchet grips in respective directions opposite tothose of D1 and D2 when the ratchet grips 10 and 12 are engaged with oneanother. In some embodiments, the first and second ratchet grips 10, 12are biased toward one another, for example by the coil element 2 actingas a spring. In other embodiments, the first and second ratchet grips10, 12 are not biased together, but remain in place against one anotherbased on the ability of the coil element 2 to reduce its inner diameteras it is twisted without elongating. The unidirectional rotationalcoupling mechanism may be referred to, in some cases, as a ratchetmechanism. The ratchet mechanism may be formed by teeth that are formedor cut into the ends of the ratchet grips 10, 12; such teeth may beundercut and/or back-cut, for example.

According to some embodiments of the present disclosure, theunidirectional rotational coupling is reversible and/or releasable. Forexample, for a coil element 2 that has undergone elastic deformation inmoving to the gripping configuration, pulling apart the first and secondratchet grips 10, 12 and then releasing one or both ratchet grips 10, 12permits the coil element 2 to unwind and release its grip from the lead4. A safety cap 16 may be included on the device 11, for example slid orotherwise positioned over the location of the unidirectional rotationalcoupling 14. The safety cap 16 prevents the mechanisms (e.g. teeth) ofthe unidirectional rotational coupling 14 from snagging or damagingsurrounding tissue, whether during primary rotation/tightening or duringrelease of the unidirectional rotational coupling 14.

When the coil element 2 is moved to the configuration in which itengages the lead 4, the coil element 2 creates a relatively large forceon the lead 4 over a large area. As the two ratchet grips 10, 12 arepulled apart, the coil element 2 may release the lead 4 and the device11 can be repositioned and re-tightened on the lead 4 body.Additionally, this embodiment may include a safety cap 16 that protectsthe physician's hands from the ratchet mechanism 14. This cap 16 may beattached to one of the ratchets 10, 12 at one end via weld joints, andmay float over the ratchet mechanism 14.

A tether T may be coupled to the body, for example to one of the firstand second ratchet grips. As shown in FIG. 3 , a tether T is coupled tothe ratchet grip 10 (length of tether T is not necessarily to scale).Tether T extends further proximally than the lead when the device 11 iscoupled with the lead. Tension applied to tether T is transmitted to thedevice 11 and thus to the lead when the device 11 is coupled to thelead. Tether T also permits an extraction device to be placed over itand advanced over the tether T to the device 11 and eventually to thelead to which device 11 is attached.

FIG. 5 illustrates a front perspective view of a cam actuation mechanismdevice 21 for a coil element 22, according to an embodiment of thepresent disclosure. FIG. 6 illustrates a partial front elevation view ofthe cam actuation mechanism device 21 of FIG. 5 showing an unwound andflattened depiction of the cam pathway 27, according to an embodiment ofthe present disclosure. The device 21 includes a coil element 22, whichmay in some embodiments include features and characteristics that arethe same as or similar to coil element 2. Device 21 includes a bodyformed by an outer sleeve 26 and an inner sleeve 28; coil element 22 iscoupled to outer sleeve 26 at end 23 (e.g. by welding), and coil element22 is coupled to inner sleeve 28 at end 24 (e.g. by welding).

During operation, the coil element 22 is placed over a lead, for exampleby placing the distal end 23 of coil element 22 over the lead. In thisfirst configuration, the coil element 22 has coils that have an innerdiameter that is larger than the outer diameter of the outer surface ofthe lead over which it is placed. Next, the coil element 22 may be movedto a second configuration in which some or all of the coils of the coilelement 22 are engaged in a gripping manner with the outer surface ofthe lead. This may be accomplished by stretching the coil element 22longitudinally, for example along a longitudinal axis of the coilelement 22, which may be aligned with the longitudinal axis of thedevice 21 and the lead onto which the device 21 is attached. In theembodiment shown in FIG. 5 , the longitudinal stretching of the coilelement 22 is achieved by translating the outer sleeve 28 away from theinner sleeve 26. The movement of the inner sleeve 26 with respect to theouter sleeve 28 may be governed by a cam actuation mechanism. The camactuation mechanism of FIGS. 5 and 6 takes the form of a cam pathway 27formed into the outer sleeve 26, within which is guided a pin 29 coupledto the inner sleeve 28. The cam pathway 27 may be formed of a slotextending through the outer sleeve 26 and/or of a groove formed withinan inner surface of the outer sleeve 26, according to an embodiment ofthe present disclosure.

The cam pathway 27 may include various sections to achieve lengthening,compression, and/or twisting of the coil element 22, according toembodiments of the present disclosure. While one example of a campathway 27 is provided, one of ordinary skill in the art, who isfamiliar with the present disclosure, will appreciate the numerouspossible cam pathways in order to move a coil element 22 to a grippingengagement with a lead. Cam pathway 27 includes a first section 27 athat extends along a substantially straight line that is substantiallyparallel to a longitudinal axis of the coil element 22 and outer andinner sleeves 26, 28. A second section 27 b generally continues toextend in a direction away from the coil element 22, while also wrappingaround the outer sleeve 26 in order to cause the inner sleeve 28 totwist or turn relative to the outer sleeve 26. A third section 27 ccauses the pin 29 to move back toward the coil element 22 whilecontinuing to cause twisting of the inner sleeve 28 relative to theouter sleeve 26. According to some embodiments, the inner sleeve 26 isbiased toward the outer sleeve 28 such that this biasing force isovercome when it is desired to pull them apart (thereby moving the coilelement 22 to the second/lead engaging position). Section 27 c of thecam pathway 27 provides an endpoint in the second configuration in whichthe pin 29 can rest and in which the pin 29 is deterred from slidingback down the pathway sections 27 b and 27 a due to the biasing,according to an embodiment of the present disclosure. In this manner,Section 27 c forms a locking mechanism which locks the pin 29 in theending position and thereby locks the coil element 22 in a configurationin which it is engaged in a gripping configuration with the lead.

Also, while end 23 of coil element 22 is described above as a distalend, the entire device 21 may alternatively be placed over and engagedwith the lead in the opposite direction, for example by placing the leadthrough the sleeve 28, then sleeve 26 and then end 24 of coil element22, according to an embodiment of the present disclosure. Furthermore,while the pin 29 is described above as being coupled with inner sleeve28 and the cam pathway 27 is described as being formed in outer sleeve26, the pin 29 may alternatively be coupled to the outer sleeve 26 andthe cam pathway 27 may alternatively be formed in the inner sleeve 28,according to an embodiment of the present disclosure.

A tether T may be coupled to the body, for example to the outer sleeve26, according to an embodiment of the present disclosure. As shown inFIG. 5 , a tether T is coupled to the outer sleeve 26 (length of tetherT is not necessarily to scale). Tether T extends further proximally thanthe lead when the device 21 is coupled with the lead. Tension applied totether T is transmitted to the device 21 and thus to the lead when thedevice 21 is coupled to the lead. Tether T also permits an extractiondevice to be placed over it and advanced over the tether T to the device21 and eventually to the lead to which device 21 is attached.

FIG. 7 illustrates a coil element 32 with a particular geometry forachieving selective tightening about a lead, according to an embodimentof the present disclosure. Coil element 32 includes a variable pitchcoil; the coil element 32 includes a tight pitch segment with tightpitch coils 36 a, 36 b and loose pitch segments 35 a, 35 b, and 35 c.When a torque is applied to twist or rotate the first end 33 and secondend 34 with respect to each other, the tight pitch coils 36 will deformor tighten onto the lead first, followed by the loose pitch segments 35at higher torque. The variable pitch coil element 32 may be positionedover leads having multiple different types of components, for exampleinsulation and high voltage cables, by positioning the appropriate pitchsegment 35, 36 over the desired area or type of component on the lead.

FIGS. 8 and 9 illustrate an outer sleeve 48 with a breakaway torque tab49, according to an embodiment of the present disclosure. The outersleeve 48 may be used with a rotational-based embodiment of a devicewith a coil element, for example with the device 11 described above.Outer sleeve 48 may be used to limit the maximum torque applied to anelement of the device, in order to prevent over-tightening and the like.Outer sleeve 48 includes a weakened, breakaway tab 49. Tab 49 may beplaced within a keyway that is cut into the particular rotational-basedpiece, for example a keyway cut into a ratchet grip 10, 12. The tab 49may include an irregular cross-section, such as the trapezoidalcross-section shown. The outer sleeve 48 and tab 49 may be slid over theratchet grip 10 or 12 while sliding the tab 49 into the keyway. When acertain amount of torque is applied to the outer sleeve 48, the shearforce between the keyway (and tab 49) and the outer sleeve 48 will causeseparation or breakaway of the tab 49 from the sleeve 48 when it exceedsa certain amount. Upon separation of the tab 49 from the outer sleeve48, the outer sleeve 48 simply rotates over the ratchet grip 10 or 12without applying further torque, so as not to over-tighten the coilelement 2 onto the lead 4, according to an embodiment of the presentdisclosure. In this way, standardizing the failure of the tab 49 at aknown force or torque provides confirmation of a positive lock of thedevice 11 onto the lead 4. Based on the present disclosure, one ofordinary skill in the art will appreciate that other configurations forthe tab and keyway are possible, and that other mechanisms may be usedto achieve a similar function. For example, the ratchet grip 10 mayinclude the tab, and the outer sleeve may include the keyway.

FIGS. 10 and 11 illustrate another embodiment of a ratchet deploymentdevice 50. The ratchet deployment device 50 may in some embodimentsinclude features and characteristics that are the same as or similar todevice 11. That is, generally, the device 50 may include ratchet grips51 and 52, a coil element 53, and a safety cap 54. The device 50 alsoincludes a trailing wire or tether T. The tether T may include, forexample, high strength braided fibers, metal wires, and the like. Thetether T allows tension to be applied to the coil element 53 from acontrol point away from the coil element 53. Tether T extends furtherproximally than the lead when the device 50 is coupled with the lead.Tension applied to tether T is transmitted to the device 50 and thus tothe lead when the device 50 is coupled to the lead. Tether T alsopermits an extraction device to be placed over it and advanced over thetether T to the device 50 and eventually to the lead to which device 50is coupled. The tether T may be coupled to one or more of the ratchetgrips 51 and 52 and the coil element 53. For example and as shown inFIGS. 10 and 11 , the tether T extends through the inner lumen of theratchet grip 52, into the inner lumen of the ratchet grip 51, and theends of the tether T couple to the inner surface of the ratchet grip 51.

While FIGS. 10 and 11 illustrate the tether T coupled to a ratchetdeployment device 50, such a tether T may be used with any of the typesof devices disclosed herein. For example, the tether T illustrated inFIGS. 10 and 11 may be used with the cam actuation mechanism device 21and/or a device including the outer sleeve 48.

A lead locking device for applying traction internally to a lead forlead removal is another example aspect of the present disclosure. A leadlocking device employing a hollow tubular member, examples of which areshown in FIGS. 12A-12D, advantageously may also provide structure andrigidity internally along a substantial portion of the length or theentire length of a lead, thereby, increasing the chance for successfulremoval when used with an extraction device externally disposed relativeto the lead. The tubular member is distortable in order to expand forlocking or otherwise fixedly engage with the internal surface of a lead.An actuation mechanism effects the distortion and is releasable orreversible to return the distorted tubular member to its original shapeas needed. Prior art lead locking devices that are not reversible mayneed to be abandoned within a lead if lead removal procedure provesunsuccessful. FIGS. 12A, 12B and 12C show some example configurations oftubular members, although as one of skill in the art would recognize,other tubular member configurations also are suitable. FIG. 12D is adistorted or expanded version of the tubular member of FIG. 12C.

FIG. 13A illustrates a top plan schematic view of a tubular member 102(which may also be referred to as a hypotube) on a body 111 in aconfiguration for sliding into a lead (not shown), according to anembodiment of the present disclosure. In the configuration of FIG. 13A,the tubular member 102 includes a plurality of segments 101, and anouter surface 108 with an outer dimension or diameter that is smallenough to be received by a lead therethrough, such that the tubularmember 102 may be placed within the lead and/or slide freely within thelead when the tubular member 102 is in an unexpanded configuration asshown in this figure. The segment of tubular member 102 depicted may bea segment of a laser cut hypotube with an interrupted spiral cut (“ISC”)pattern. The plurality of segments may be formed by, for example, ISC,coil cut pattern, and/or the like. The tubular member 102 may beexpanded from the unexpanded configuration shown in FIG. 13A to theexpanded configuration shown in FIG. 13B in which some or all of theplurality of segments 101 of the tubular member 102 are expanded,relaxed or released such that they engage and grip with an inner surfaceof a lead. In some embodiments, the expansion of the tubular member 102results in compressive or expansive force being applied to the innersurface of the lead.

The tubular member 102 may be moved between a first configuration (e.g.,unexpanded configuration) in which the tubular member 102 slides into orwithin a lead to a second configuration (e.g., expanded configuration)in which some or all of the segments of the tubular member 102grippingly engage the inner surface of the lead in various ways. As oneexample, the tubular member 102 may be springably released, therebycausing the outer surface of the segments to expand to engage the lead.As another example, one end of the tubular member 102 may be rotated,twisted, or turned with respect to the other end of the tubular member102 in order to forcibly, springably or naturally cause a loosening ofthe windings of the segments of the tubular member 102, therebyexpanding their outer diameters to the point at which the tubular memberengages the inner surface of the lead.

FIG. 13B illustrates the tubular member 102 in an expandedconfiguration, in which the laser cut segment with interrupted spiralcut (“ISC”) pattern has been expanded to engage the inner surface of alead. A trailing wire or tether (not shown), including for example highstrength braided fibers, metal wires, and the like, may be attached tothe tubular member 102 to allow tension to be applied to the tubularmember 102 from a control point away from the tubular member 102 and thelead itself. Tubular member 102 is made of a material suited for lasercutting, for example, stainless steel. Shape memory alloys are suitablefor tubular member 102 including nickel titanium alloys. Other alloysincluding for example, nickel, titanium, copper, zine, aluminum, orcombinations thereof, are suitable for tubular member 102 provided thealloy selected is biocompatible. Characteristics important in choosingthe material for tubular member 102 include hardness and tensilestrength. As tubular member sizes are required to be ever smaller forapplications within patients' vessels, material selection is importantto prevent tearing or pulling apart of the laser cut tubular member.

The tubular member includes a series of radially expandable, elasticsections that are substantially relaxed in the first configuration andradially expanded under a compressive force in the second configuration.In an example aspect, sections are uniformly repeated. In anotherexample aspect, each section is variable. In another example aspect, twoor more sections repeat alternatively. Sections may be cut or uncut. Asone of skill in the art would recognize, each section can have variousshapes. In an example aspect, sections include segments of variousshapes or configurations such as, but not limited to, ring, spiral,diamond, parallel cuts, six-sided bodies, other such shapes, orcombinations thereof. Sections may combine to form a helically orientedpathway including a plurality of open sections alternatingly disposedwith bridge members so that if laid flat (or unrolled) the tubularmember would appear as in one connected sheet. Varying pitches may beemployed to provide sections of more rigidity or more flexibility. Atubular member configuration including varying cut patterns, sections,and pitches, some repeated, advantageously provide a tubular memberconfigured to sequentially expand from one end of a length to the other,or alternatively from a section located within the tubular length or themiddle of the tubular length to expand sequentially outwardly. Forexample, it may be desirable to deploy the tubular member to expandfirstly at a tip to secure positioning, prior to sequentially expandingthe tubular member to engage with the entire length of the lead innersurface thereby providing maximum traction.

In an example aspect of the present disclosure, a majority of thesegments engage the inner lumen of the lead. In one embodiment,substantially all of the segments engage the inner lumen of the lead.The tubular member may be laser cut to achieve desired shape or pitch orboth. Advantageously, the tubular member is releasable, repositionable,and reversible. In other words, the tubular member may be relaxed backto the first configuration, thus allowing for replacing or repositioningas necessary to provide the user with more control and better tractionfor removing, extending, or extracting the lead.

Referring to FIG. 14A and FIG. 14B, in an example aspect, a device forextending a lead is provided. The device 150 comprises body 111, tubularmember 102 coupled to body 111. The tubular member 102 comprises anouter surface 108 (as shown in FIG. 13A), wherein the dimension(s) ofthe tubular member 102, including the outer surface, is sized to insertinto inner lumen 106 of lead 105. Tubular member 102 is movable betweena first configuration (e.g., unexpanded configuration) (as shown in FIG.14A) in which the tubular member slides into or within lead 105, and asecond configuration (e.g., expanded configuration) (as shown in FIG.14B) in which at least a portion of tubular member 102 expands to engageinner surface 106 of lead 105.

In an example aspect, an actuation mechanism is operatively coupled totubular member 102, wherein the actuation mechanism is configured tomove the tubular member 102 between the first configuration and secondconfiguration (and potentially back to the first configuration after thetubular member is in the second configuration). In an example aspect,the tubular member comprises a plurality of segments 101. In an example,at least some segments 101 of the plurality of segments springablyrelease to sequentially engage inner surface 106 of lead 105 from adistal-most end 103 of the lead to a proximal-most end of the lead. Inanother example aspect, at least some segments 101 of the plurality ofsegments springably release to sequentially engage inner surface 106 oflead 105 from a proximal-most end of the lead to distal-most end 103 ofthe lead. In a further example, at least some segments 101 of theplurality of segments springably release to simultaneously engage theinner surface 106 of the lead 105. In an example aspect, the tubularmember 102 includes a distal-most end that is aligned with a distal-mostend of the lead 103. In an example aspect, the tubular member engagesthe entire longitudinal length of the lead.

Different actuation mechanisms are employable to distort the tubularmember including, but not limited to, friction or interference fit,slide coin, twist and deploy, or screw compression/extension mechanisms.FIG. 15 illustrates an embodiment wherein body 111 is a ratchetdeployment device. In an example aspect, the ratchet deployment deviceincludes inner sleeve 228 and outer sleeve 226 and, optionally, atrailing wire or tether T. The tether T may include, for example, highstrength braided fibers, metal wires, and the like. The tether T allowstension to be applied to the tubular member 102 from a control pointaway from the tubular member 102. Tether T extends further proximallythan the lead when the device is coupled with the lead. Tension appliedto tether T is transmitted to the device and thus to the lead when thedevice is coupled to the lead. The tether T may be coupled to one ormore of the ratchet grips 226 and 228 and the tubular member 102. WhileFIG. 15 illustrates the tether T coupled to a ratchet deployment device,such a tether T may be used with any of the types of devices disclosedherein. For example, the tether T illustrated in FIG. 15 may be usedwith a cam actuation mechanism device. In an example aspect, the devicefurther comprises a tether coupled to a lead via one or more of thebody, the tubular member, and the actuation mechanism, the tetherconfigured to extend further proximally than a proximal-most end of thelead, the tether further configured to transfer at least a portion of atension force applied to the tether to the lead via the one or more ofthe body, the tubular member, and the actuation mechanism.

FIG. 16A and FIG. 16B illustrate one embodiment of a ratchet deploymentdevice 211, with an external laser-cut tubular member 202 and ratchetgrips 210, 212. In the embodiment shown in FIGS. 16A and 16B, ratchetgrip 210 is coupled to end 208 of tubular member 202 (e.g. by welding)within an interior lumen of tubular member 202, and ratchet grip 212 iscoupled to end 206 of tubular member 202 (e.g. by welding) within aninterior lumen of tubular member 202. Ratchet grips 210 and 212interface with each other at unidirectional rotational coupling 214,which may be formed by teeth or other interengaging projections andindentations which permit ratchet grip 210 to rotate in direction D1with respect to ratchet grip 212, and which permit ratchet grip 212 torotate in direction D2 with respect to ratchet grip 210, but whichinhibit rotation of such ratchet grips in respective directions oppositeto those of D1 and D2 when the ratchet grips 210 and 212 are engagedwith one another. In some embodiments, the first and second ratchetgrips 210, 212 are biased toward one another, for example by the tubularmember 202 acting as a spring. In other embodiments, the first andsecond ratchet grips 210, 212 are not biased together, but remain inplace against one another based on the ability of the tubular member 202to increase its outer diameter as it is twisted without elongating. Theunidirectional rotational coupling mechanism may be referred to, in somecases, as a ratchet mechanism. The ratchet mechanism may be formed byteeth that are formed or cut into the ends of the ratchet grips 210,212; such teeth may be undercut and/or back-cut, for example.

According to some embodiments of the present disclosure, theunidirectional rotational coupling is reversible and/or releasable. Forexample, for a tubular member 202 that has undergone elastic deformationin moving to the expanded configuration, pulling apart the first andsecond ratchet grips 210, 212 allows the release of one or both ratchetgrips 210, 212, thereby permitting the tubular member 202 to rewind andspringably disengage the lead. When the tubular member 202 is moved tothe configuration in which it engages the lead, the tubular member 202creates a relatively large force on the inner surface of the lead over alarge area. In an example aspect, the tubular member is releasable andrepositionable for further use. In other words, as the two ratchet grips210, 212 are pushed together or pulled apart, the tubular member 202 mayrelease the device 211 from the lead so that the device 211 can berepositioned and re-aligned within the lead body. According to someembodiments of the present disclosure, a bidirectional coupling mayreplace the unidirectional rotational coupling.

A tether T may be coupled to the body, for example to one of the firstand second ratchet grips. As shown in FIG. 16A, a tether T is coupled tothe ratchet grip 210 (length of tether T is not necessarily to scale).Tether T extends further proximally than the lead when the device 211 iscoupled with the lead. Tension applied to tether T is transmitted todevice 211 and thus to the lead when device 211 is coupled to the lead.Tether T also permits an extraction device to be placed over it andadvanced over the tether T to device 211 and eventually to the lead towhich device 211 is attached.

In an example aspect, the actuation mechanism comprises a first ratchetgrip and a second ratchet grip, wherein the first ratchet grip iscoupled to a first end of the tubular member, wherein the second ratchetgrip is coupled to a second end of the tubular member. In an exampleaspect, the actuation mechanism is configured to move the tubular memberbetween first and second configurations via one or both of thefollowing: rotation of the first ratchet grip along a first rotationaldirection relative to the second ratchet grip; and rotation of thesecond ratchet grip along a second rotational direction relative to thefirst ratchet grip, wherein the first and second rotational directionsare opposing rotational directions. In an example aspect, the firstratchet grip engages the second ratchet grip at a unidirectionalrotational coupling that permits rotation of the first ratchet gripalong the first rotational direction relative to the second ratchet gripand rotation of the second ratchet grip along the second rotationaldirection relative to the first ratchet grip while inhibiting rotationof the first ratchet grip along the second rotational direction relativeto the second ratchet grip and of the second ratchet grip along thefirst rotational direction relative to the first ratchet grip while thefirst ratchet grip is in the unidirectional rotational coupling with thesecond ratchet grip. In an example aspect, the unidirectional rotationalcoupling includes one or more undercut or back-cut teeth formed on oneor both of the first and second ratchet grips. In an example aspect, thefirst and second ratchet grips are axially separable from one another torelease the unidirectional rotational coupling, thereby permitting thetubular member to move from a configuration in which the tubular memberouter surface, having an outer diameter, is minimized to an expandedconfiguration.

In an example aspect, the device comprises an inner sleeve, a keywayformed in one of the inner sleeve and the first ratchet grip, and a tabformed in the other of the inner sleeve and the first ratchet grip,wherein torque is transmitted from the inner sleeve to the first ratchetgrip via an interface between the keyway and the tab, the tab configuredto break away from the inner sleeve at a level of applied torque. In anexample aspect, the actuation mechanism is the body. The keyway and tabmechanism is similar as shown in FIG. 8 and FIG. 9 .

FIG. 17A illustrates a front perspective view of a cam actuationmechanism device 221 for a tubular member 222, according to anembodiment of the present disclosure. FIG. 17B illustrates a partialfront elevation view of the cam actuation mechanism device 221 of FIG.17A showing an unwound and flattened depiction of the cam pathway 227,according to an embodiment of the present disclosure. The device 221includes a tubular member 222, which may in some embodiments includefeatures and characteristics that are the same as or similar to tubularmember 202. Device 221 includes a body formed by an outer sleeve 226 andan inner sleeve 228; tubular member 222 is coupled to outer sleeve 226at end 223 (e.g. by welding), and tubular member 222 is coupled to innersleeve 228 at end 224 (e.g. by welding).

During operation, the tubular member 222 is placed within a lead, forexample by placing the distal end 223 of tubular member 222 into thelead. In this first configuration, tubular member 222 has coils thathave an outer diameter that is smaller than the diameter of the innersurface of the lead into which it is placed. Next, tubular member 222may be moved to a second configuration in which some or all of thesegments of tubular member 222 are springably released to engage in agripping manner with the inner surface of the lead. This may beaccomplished by moving the tubular member 222 longitudinally from atightly wound configuration, for example along a longitudinal axis ofthe tubular member 222, which may be aligned with the longitudinal axisof the device 221 and the lead into which the device 221 is engaged. Inthe embodiment shown in FIG. 17A, the expanding of the tubular member222 is achieved by translating the outer sleeve 228 toward the innersleeve 226. The movement of the inner sleeve 226 with respect to theouter sleeve 228 may be governed by a cam actuation mechanism. The camactuation mechanism of FIGS. 17A and 17B takes the form of a cam pathway227 formed into the outer sleeve 226, within which is guided a pin 229coupled to the inner sleeve 228. The cam pathway 227 may be formed of aslot extending through the outer sleeve 226 and/or of a groove formedwithin an inner surface of the outer sleeve 226, according to anembodiment of the present disclosure.

The cam pathway 227 may include various sections to achieve lengthening,expanding, and/or twisting of the tubular member 222, according toembodiments of the present disclosure. While one example of a campathway 227 is provided, one of ordinary skill in the art, who isfamiliar with the present disclosure, will appreciate the numerouspossible cam pathways in order to move a tubular member 222 to agripping engagement with a lead. Cam pathway 227 includes a firstsection 227 a that extends along a substantially straight line that issubstantially parallel to a longitudinal axis of the tubular member 222and outer and inner sleeves 226, 228. A second section 27 b generallycontinues to extend in a direction toward the tubular member 222, whilealso wrapping around the outer sleeve 226 in order to cause the innersleeve 228 to twist or turn relative to the outer sleeve 226. A thirdsection 227 c causes the pin 229 to move away from the tubular member222 while continuing to cause twisting of the inner sleeve 228 relativeto the outer sleeve 226. According to some embodiments, the inner sleeve226 is biased toward the outer sleeve 228 such that this biasing forceis overcome when it is desired to push them together (thereby moving thetubular member 222 to the second/lead engaging position). Section 227 cof the cam pathway 227 provides an endpoint in the second configurationin which the pin 229 can rest and in which the pin 229 is deterred fromsliding back down the pathway sections 227 b and 227 a due to thebiasing, according to an embodiment of the present disclosure. In thismanner, Section 227 c forms a locking mechanism which locks the pin 229in the ending position and thereby locks the tubular member 222 in aconfiguration in which it is engaged in a gripping configuration withthe lead.

A tether T may be optionally coupled to the body, for example to theouter sleeve 226, according to an embodiment of the present disclosure.As shown in FIG. 17A, a tether T is coupled to the outer sleeve 226(length of tether T is not necessarily to scale). Tether T extendsfurther proximally than the lead when the device 221 is coupled with thelead. Tension applied to tether T is transmitted to the device 221 andthus to the lead when the device 221 is coupled to the lead. Tether Talso permits an extraction device to be placed over it and advanced overthe tether T to the device 221 and eventually to the lead to whichdevice 221 is attached.

In an example aspect of the present disclosure, the device includes abody comprising a first sleeve and a second sleeve, wherein the firstsleeve is coupled to a first end of the tubular member, wherein thesecond sleeve is coupled to a second end of the tubular member, andwherein the actuation mechanism is configured to move the tubular memberbetween the first and second configurations via axial translation of thefirst sleeve along a direction relative to the second sleeve. In anexample aspect, the actuation mechanism further comprises a pin coupledto one of the first and second sleeves and a slot formed in another ofthe first and second sleeves, wherein the slot guides a path oftranslation of the first sleeve with respect to the second sleeve. In anexample aspect, the slot includes a portion that imparts a tighteningtwist to the tubular member in moving the tubular member to the secondconfiguration. In an example aspect, the direction is a first direction,and wherein the slot includes a portion that causes translation of thefirst sleeve along a second direction relative to the second sleeve inmoving the tubular member to the second configuration, wherein thesecond direction is different from the first direction. In an exampleaspect, the second direction is opposite to the first direction. In anexample aspect, the plurality of segments include segments of differentpitch (as shown in FIG. 7 ), such that some of the plurality of segmentsare configured to expand to springably engage the lead at a lowerapplied torque than others of the plurality of segments. In anotherexample, the actuation mechanism is configured for mechanicalengagement. An inner sleeve having outwardly protruding dimples, forexample, friction fits into the outer sleeve of the actuation mechanism.In an alternative example, the actuation mechanism friction fits to thetubular member. The actuation mechanism can be advantageously configuredfor bidirectional movement for deployment or distortion of the tubularmember and for release or restoring the tubular member to originalstate.

In an example aspect of the present disclosure, a method is provided.The method includes extending a lead comprising the steps: sliding atubular member into a lead when the tubular member is in a firstconfiguration, the tubular member comprising an outer surface sized toinsert into an inner lumen of the lead; moving the tubular member fromthe first configuration into a second configuration in which at least aportion of the tubular member expands to engage the inner lumen of thelead by actuating an actuation mechanism operatively coupled to thetubular member, the actuation mechanism configured to move the tubularmember between the first configuration and the second configuration. Inan example aspect of the method, the tubular member comprises aplurality of segments. In an example aspect of the method, at least somesegments of the plurality of segments springably release to sequentiallyengage the inner surface of the lead from a distal-most end of the leadto a proximal-most end of the lead or from a proximal-most end of thelead to a distal-most end of the lead. In an example aspect of themethod, the actuation mechanism comprises a first ratchet grip and asecond ratchet grip, wherein the first ratchet grip is coupled to afirst end of the tubular member, wherein the second ratchet grip iscoupled to a second end of the tubular member, and wherein manipulatingthe actuation mechanism to move the tubular member from the firstconfiguration into the second configuration includes one or both of:rotating the first ratchet grip along a first rotational directionrelative to the second ratchet grip, and rotating the second ratchetgrip along a second rotational direction relative to the first ratchetgrip, wherein the first and second rotational directions are opposingrotational directions. In an example aspect of the method, the tubularmember includes a first end coupled to a first sleeve and a second endcoupled to a second sleeve, and wherein manipulating the actuationmechanism to move the tubular member from the first configuration intothe second configuration includes translating the first sleeve along adirection relative to the second sleeve. In an example aspect of themethod, the actuation mechanism further comprises a pin coupled to oneof the first and second sleeves and a slot formed in another of thefirst and second sleeves, the slot guiding a path of translation of thefirst sleeve with respect to the second sleeve, and wherein manipulatingthe actuation mechanism to move the tubular member from the firstconfiguration into the second configuration causes the slot to impart areleasing twist to the tubular member. In an example aspect of themethod, the plurality of segments include segments of a first pitch andsegments of a second pitch, and moving the tubular member from the firstconfiguration into the second configuration includes releasing thesegments of the first pitch to springably engage the inner lumen of thelead at a first applied torque and releasing the segments of the secondpitch to springably engage the inner lumen of the lead at a secondapplied torque, the second applied torque being less than the firstapplied torque.

In the appended figures, similar components and/or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a letter thatdistinguishes among the similar components. If only the first referencelabel is used in the specification, the description is applicable to anyone of the similar components having the same first reference labelirrespective of the second reference label.

A number of variations and modifications of the disclosure may be used.It would be possible to provide for some features of the disclosurewithout providing others.

The present disclosure, in various aspects, embodiments, and/orconfigurations, includes components, methods, processes, systems and/orapparatus substantially as depicted and described herein, includingvarious aspects, embodiments, configurations embodiments, subcombinations, and/or subsets thereof. Those of skill in the art willunderstand how to make and use the disclosed aspects, embodiments,and/or configurations after understanding the present disclosure. Thepresent disclosure, in various aspects, embodiments, and/orconfigurations, includes providing devices and processes in the absenceof items not depicted and/or described herein or in various aspects,embodiments, and/or configurations hereof, including in the absence ofsuch items as may have been used in previous devices or processes, e.g.,for improving performance, achieving ease and/or reducing cost ofimplementation.

The foregoing discussion has been presented for purposes of illustrationand description. The foregoing is not intended to limit the disclosureto the form or forms disclosed herein. In the foregoing Summary forexample, various features of the disclosure are grouped together in oneor more aspects, embodiments, and/or configurations for the purpose ofstreamlining the disclosure. The features of the aspects, embodiments,and/or configurations of the disclosure may be combined in alternateaspects, embodiments, and/or configurations other than those discussedabove. This method of disclosure is not to be interpreted as reflectingan intention that the claims require more features than are expresslyrecited in each claim. Rather, as the following claims reflect,inventive aspects lie in less than all features of a single foregoingdisclosed aspect, embodiment, and/or configuration. Thus, the followingclaims are hereby incorporated into this Summary, with each claimstanding on its own as a separate embodiment of the disclosure.

Moreover, though the description has included description of one or moreaspects, embodiments, and/or configurations and certain variations andmodifications, other variations, combinations, and modifications arewithin the scope of the disclosure, e.g., as may be within the skill andknowledge of those in the art, after understanding the presentdisclosure. It is intended to obtain rights which include alternativeaspects, embodiments, and/or configurations to the extent permitted,including alternate, interchangeable and/or equivalent structures,functions, ranges or steps to those claimed, whether or not suchalternate, interchangeable and/or equivalent structures, functions,ranges or steps are disclosed herein, and without intending to publiclydedicate any patentable subject matter.

What is claimed is:
 1. A lead locking device, comprising: a tubular member configured to engage a lead; a first ratchet grip coupled to the tubular member; and a second ratchet grip coupled to tubular member, wherein the first ratchet grip and the second ratchet grip are configured to interface with one another at a rotational coupling, wherein the rotational coupling is configured to: permit rotation of the first ratchet grip relative to the second ratchet grip in a first direction; and inhibit rotation of the first ratchet grip relative to the second ratchet grip in an opposite, second direction.
 2. The device of claim 1, wherein the tubular member is configured to be positioned internally relative to the first ratchet grip and the second ratchet grip.
 3. The device of claim 1, wherein the tubular member comprises a coil.
 4. The device of claim 1, wherein the tubular member comprises a first end and an opposite, second end, wherein the first ratchet grip is coupled to the first end, and wherein the second ratchet grip is coupled to the second end.
 5. The device of claim 1, wherein the rotational coupling comprises: a first engagement feature of the first ratchet grip; and a second engagement feature of the second ratchet grip.
 6. The device of claim 5, wherein the first engagement feature is positioned at a first end of the first ratchet grip and the second engagement feature is positioned at an opposite second end of the second ratchet grip.
 7. The device of claim 5, wherein the first engagement feature and the second engagement feature each comprise at least one of a projection or an indentation.
 8. The device of claim 7, wherein the projection comprises an undercut tooth or back-cut tooth.
 9. The device of claim 1, wherein the first ratchet grip and the second ratchet grip are biased toward one another.
 10. The device of claim 1, wherein the first ratchet grip and the second ratchet grip are not biased toward one another.
 11. The device of claim 1, wherein the rotational coupling is reversible.
 12. The device of claim 11, wherein the first ratchet grip and the second ratchet grip are configured to be pulled apart such that the tubular member is configured to release the lead.
 13. The device of claim 1, further comprising a safety cap configured to be positioned over the rotational coupling.
 14. The device of claim 13, wherein the safety cap is coupled to the first ratchet grip or the second ratchet grip.
 15. The device of claim 1, further comprising a tether coupled to the first ratchet grip or the second ratchet grip. 